联合DOA估计与主波束形成的干扰抑制方法

Interference mitigation method based on joint DOA estimation and main beam forming

摘要:

为克服测距仪(DME)发射的高强度脉冲信号干扰L频段数字航空通信系统1(L-DACS1)OFDM接收机的问题，提出联合DOA估计与主波束形成的干扰抑制方法.首先接收机通过波达方向矩阵算法估计接收信号来向；然后基于信号来向通过线性约束最小方差波束形成算法提取各个方向信号；随后通过频域功率与时域功率比较算法分辨各来向信号的类型；最后输出OFDM直射径信号.仿真结果表明：该方法可显著克服DME与OFDM散射径信号干扰，提高L-DACS1系统链路传输的可靠性.

Abstract:

To mitigate the deleterious influence of Distance Measure Equipment (DME) interference on Orthogonal Frequency Division Multiplexing (OFDM) receiver of L-band Digital Aeronautical Communications System1(L-DACS1) operating as an inlay system, a new interference suppression method is proposed based on joint DOA estimation and main beamforming. Firstly, DOA matrix algorithm is used to estimate the DOA of the received signals. Secondly, with the DOA information, Linearly Constrained Minimum Variance(LCMV) beamforming algorithm is utilized to extract the signals in all directions. Finally, frequency-domain power comparison and time-domain power comparison method is proposed to distinguish the received signals and output the direct line-of-sight(LOS) path OFDM signal. Computer simulation results indicate that the proposed method can effectively overcome DME impulse interference and OFDM scattering signal and improve the reliability of the L-DACS1 system.